Radical radiotherapy for carcinoma of the uterine cervix using external beam radiotherapy and a single line source brachytherapy technique: the Clatterbridge technique

At the Clatterbridge Centre for Oncology, a single line source brachytherapy technique using the Selectron (Nucletron) low dose rate remote afterloading equipment has been developed for use in conjunction with homogenous whole pelvis external beam radiotherapy in the radical treatment of carcinoma of the cervix. The technique incorporates several modifications aimed at reducing treatment related morbidity while maintaining satisfactory local tumour control and cure rates. A flexible dose prescription system has been devised to allow individualization of the brachytherapy isodose distribution according to the clinical findings and the estimated normal tissue doses. Modifications of source loading distributions are carried out to limit the point "A" dose rate to a narrow range to take into account the dose rate effect on the risk of complications. Source loading distributions are also modified according to the estimated normal tissue doses in order to respect normal tissue tolerance. This paper describes the technique and its underlying principles.

Detection of pulmonary emboli and associated right heart dysfunction by combining ventilation perfusion lung scanning and xenon ventriculography

PURPOSE

The authors sought to determine if the right ventricular ejection fraction (RVEF), as measured by xenon ventriculography, is depressed in patients with pulmonary emboli. The authors also sought to correlate any decrement in RVEF with the extent of lung perfusion defects.

MATERIALS AND METHODS

The authors identified all patients who had lung ventilation-perfusion (V/Q) scans between January 1994 and December 1996, that were interpreted as high probability for pulmonary embolism. From these patients, the authors selected those who had undergone concurrent xenon ventriculography (XV) (n = 23), and then reprocessed the initial ventriculography data for confirmation. The authors also reviewed original V/Q scans, chest radiographs, and clinical data. A control group was drawn from patients with normal V/Q scans who had undergone XV.

RESULTS

Fifteen patients (65%) with high probability V/Q scans had an abnormally low RVEF (< .32). Patients with high probability V/Q scans also had a significantly lower mean RVEF (0.28 +/- .08) than patients with normal V/Q scans (.39 +/- .08 SD). The degree of RVEF decline correlated poorly with the number of segmental perfusion defects (r = -.39).

CONCLUSIONS

RVEF is often depressed in patients with high probability V/Q scans. XV can identify these patients, while routine lung V/Q scans cannot.

The accuracy of CT staging of small bowel adenocarcinoma: CT/pathologic correlation

PURPOSE

Several studies have documented the use of CT in the evaluation of small bowel neoplasms, but few have addressed the CT staging of adenocarcinoma. We retrospectively correlated CT and pathologic staging to evaluate the accuracy of CT for staging small bowel adenocarcinoma using American Joint Committee on Cancer criteria.

METHOD

The preoperative CT scans of 15 patients with pathologically proven small bowel adenocarcinoma were analyzed. Two blinded readers separately interpreted extent of invasion, presence of lymphadenopathy, and distant metastases. Pathologic and CT staging were compared.

RESULTS

The overall accuracy of CT staging was 47% (14/30). The sensitivity of detection of mesenteric infiltration was 88%. The sensitivity and specificity for detection of distant metastases were 58 and 63% and for lymphadenopathy 75 and 20%, respectively. Errors occurred in patients with Crohn disease, adenomas, Peutz-Jegher syndrome, small bowel obstruction, and perforation and on suboptimal studies.

CONCLUSION

The accuracy of CT staging of small bowel adenocarcinoma is 47%. CT is highly sensitive but not specific for the detection of mesenteric infiltration and regional lymphadenopathy. Since spiral CT may offer improved detection of distant metastases and increased accuracy in the evaluation of patients with concomitant bowel disease, further research is needed to determine the maximal utility of CT in the staging of adenocarcinoma of the small bowel.

The CT halo sign: a new finding in intestinal lymphangiectasia

A "halo sign" has been described in patients with Crohn disease, ulcerative colitis, radiation enteritis, ischemic colitis, and pseudomembranous colitis. This sign is characterized by an inner ring of low CT attenuation surrounded by a higher attenuation outer ring. We present a patient with primary intestinal lymphangiectasia in whom CT demonstrated a halo sign correlated with mucosal biopsy.

Hepatitis G virus and fulminant hepatic failure: evidence for transfusion-related infection

BACKGROUND/AIMS

In the majority of cases of fulminant "viral" hepatitis in Australia, no known aetiological agent can be isolated. We have examined the possible role of the recently discovered hepatitis G virus (HGV) in such cases.

METHODS

An HGV specific reverse transcription polymerase chain reaction (RT-PCR) was performed on pre- and post-liver transplant serum from 14 patients who were referred for transplantation at our unit between 1989 and 1995 for unexplained fulminant hepatic failure. Eleven patients successfully underwent transplantation and three died while waiting for a suitable donor organ. Hepatitis viruses A-E were excluded by standard serological and PCR based testing. HGV RT-PCR was also performed on 21 other, randomly selected, liver transplant recipients ("controls").

RESULTS

The 14 fulminant cases were HGV RT-PCR negative prior to transplantation while five of 21 controls were positive. Post-transplant, eight of the 11 fulminant patients were found to be HGV RT-PCR positive and the same five controls remained HGV RT-PCR positive. In three of the eight fulminant patients the HGV infection resolved.

CONCLUSIONS

Our data indicate that HGV infection is unlikely to be responsible for fulminant hepatitis and that it is probably acquired from blood and/or blood products during the transplantation process. Furthermore, long-term carriage of HGV post-transplant is not associated with clinically apparent liver disease.

Treatment-patient interactions for diagnostics of cross-over trials

In cross-over trials, various types of responses may be recorded, not all of which can be appropriately modelled by a Normal distribution. Widening the class of models to the generalized linear model family has a number of advantages. An important one is that certain interactions, especially that between patients and treatments, can easily be fitted for frequency and count data. These can be used as diagnostics for the fit of the model used. One handicap has been the frequentist difficulty of comparing the fit of different non-nested models in this family. This can be overcome by the use of a model selection criterion such as the Akaike or Bayesian information criterion. This approach to modelling and diagnostics for cross-over trials is applied to two studies involving small counts of anginal attacks, previously analysed in the literature using classical Normal techniques.

A case of rapidly expanding tuberculous lung cavity after bronchoscopy

A non-smoking Asian woman with previously treated pulmonary tuberculosis presented with a recent onset unproductive cough and cavitating mass lesion on her chest X-ray which rapidly developed into a large tuberculous cavity after bronchoscopy. Acid-fast bacilli were isolated from the cavity and she responded very rapidly to standard anti-tuberculous chemotherapy. This unusual condition must be considered in patients who deteriorate after bronchoscopy.

Constraints on the nucleus and dust properties from mid-infrared imaging of comet Hyakutake

We use Mie scattering theory to determine the expected thermal emission from dust grains in cometary comae and apply these results to mid-infrared images of comet Hyakutake (C/1996 B2) obtained preperihelion in 1996 March. Calculations were performed for dust grains in the size range from 0.1 to 10 micrometers for two different compositions: amorphous olivine (a silicate glass) and an organic residue mixture. The resulting emission efficiencies are complicated functions of wavelength and particle size and are significantly different for the two materials in question. The Hyakutake data set consists of three nights of high-resolution imaging (100-150 km pixel-1 at the comet) of the inner coma at 8.7, 11.7, 12.5, and 19.7 micrometers. Attempts to fit the observed colors (ratios of fluxes at different wavelengths) using a single grain composition failed. However, fits to the data were achieved for all three nights using a mixture of approximately 1 micrometer olivine grains and approximately 7 micrometers organic grains. The resulting olivine mass fraction was between 8% and 16% of the total dust mass-loss rate. We also estimate the radius of the nucleus to be r = 2.1 +/- 0.4 km.

Nurses, the next generation. Who will they be and probably more important from where will they come?

What are the influences behind falling enrolments into professional nursing pre-service programs and how can the trend be reversed? Bronwyn Jones looks at the issue.

Pituitary tumours presenting in the elderly: management and outcome

OBJECTIVE

In elderly patients there are few data on the efficacy and safety of pituitary surgery and radiotherapy (DXT). The aim of the present study was to assess the mode of presentation, treatment and outcome of patients > 64 years with a pituitary tumour presenting to a regional neuroendocrine service.

DESIGN

A retrospective case note review of all patients with a pituitary tumour, from 1986 to 1993, was performed with DXT information from computerized records.

PATIENTS

Forty-four patients were identified: median age 70 (65-83) years; 25 males; followed for a mean of 34 (range 0-84) months.

RESULTS

The commonest presenting symptom was with visual disturbance (24 patients) with a further 9 with asymptomatic visual field defects. Five patients had acromegaly and two prolactinoma. Thirty-two patients underwent transsphenoidal surgery (TSS) (with post-operative DXT in 14 cases) and 6 craniotomy. Two patients had DXT as the primary procedure and four were observed. Visual fields improved in 21 of 29 patients. Perioperative complications occurred significantly more often after craniotomy (5/6) than after TSS (6/32) (P < 0.01). Eight patients died during the follow-up period (three deaths tumour related; one death followed DXT).

CONCLUSIONS

Pituitary adenoma is a remediable cause of visual disturbance in the elderly. Most tumours were non-functioning. Age alone is not a contraindication to active treatment particularly with transsphenoidal surgery and radiotherapy.

Affinity and kinetics of the interactions between an alphabeta T-cell receptor and its superantigen and class II-MHC/peptide ligands

Immune activation is mediated by a specific interaction between the T-cell receptor (TCR) and an antigenic peptide bound to the major histocompatibility complex (MHC). T-cell activation can also be stimulated by superantigens which bind to germline-encoded variable domain sequences of certain TCR beta-chains. We have used a surface plasmon resonance biosensor to characterize the molecular interactions between a class II-restricted alphabeta TCR and its superantigen and MHC/peptide ligands. The extracellular domains of the murine D10 TCR (Valpha2, Vbeta8.2) were expressed in insect cells and secreted as a disulfide-linked heterodimer. In the absence of MHC class II, purified soluble D10 TCR bound to Staphylococcus aureus enterotoxin C2 with an association rate of 1.69+/-0.12 x 10(4)M(-1) sec(-1) and a dissociation rate of 1.9+/-0.47 x 10(-2) sec(-1), giving a dissociation constant of 1.1 microM. Binding of the TCR to S. aureus enterotoxin B was barely detectable and could not be measured accurately due to the rapid dissociation rate. Soluble D10 TCR also bound to a soluble murine MHC class II I-A(k) molecule containing a fused antigenic conalbumin peptide and complementary leucine zipper sequences to facilitate efficient chain pairing. The purified I A(k) chimera specifically stimulated proliferation of the D10 T-cell clone, and bound to immobilized soluble D10 TCR with an association rate of 1.07+/-0.19 x 10(4)M(-1)sec(-1) and a dissociation rate of 2.2+/-0.65 x 10(-2) sec(-1), giving a dissociation constant of 2.1 microM.

Long-term vascular access for hemodialysis using silicon dual-lumen catheters with guidewire replacement of catheters for technique salvage

Difficulties in creating vascular access in patients on hemodialysis are encountered in most dialysis centers. This is usually due to a lack of suitable peripheral vessels due to previous access surgery in patients on long-term hemodialysis, but also may be seen in some patients de novo, particularly diabetics and patients with peripheral vascular disease. Surgical techniques used to overcome this problem vary depending on patient characteristics and, to a certain extent, on local expertise/preference. We report our experience of using silicon dual-lumen hemodialysis catheters over a 3-year period; during this time, 54 catheters were inserted into 32 hemodialysis patients. The indication for this procedure in 52 catheters (31 patients) was either exhausted vascular access or obvious difficulty identifying a suitable peripheral blood vessel. Of the catheters inserted, 20 were placed into subclavian veins by primary insertion (ie, patients did not have existing subclavian catheter); 34 were replaced over a guidewire (a procedure used to allow technique salvage). The catheter survival rate was 72.7% at 90 days and 48.7% at 1 year. Corresponding rates at 90 days and 1 year for technique survival were 93.3% and 81.8%, respectively. The mean catheter and technique survival was 387 (95% confidence intervals [CIs], 273, 502) and 844 (95% CIs, 684, 1,005) days, respectively. Poor flow accounted for 70.4% of catheter failures and, despite 18 episodes of catheter-related sepsis, no catheters were lost due to infection. Factors identified as leading to reduced catheter survival were left-sided placement and catheter tip placement in the superior vena cava (as opposed to right atrial placement). We did not observe poorer survival or increased sepsis in catheters replaced over a guidewire, and would advocate this technique as a means of salvage in this group of patients.

Age, gender and the effectiveness of high-threat letters: an analysis of Oregon's driver improvement advisory letters

The Oregon Driver Improvement Program monitors driver records and takes corrective action at each of four levels. The advisory letter is the first level. An automated quality control system randomly withholds actions from five percent of drivers, producing a control group. Records of 27,026 advisory letter recipients and 1453 control subjects were analyzed. Of the 27,026 letter recipients, 13,623 received a randomly assigned, experimental soft-sell letter and the rest a standard letter. Records were monitored for 24 subsequent months. Overall, those receiving either advisory letter had fewer traffic accidents than the control group, and the standard letter is significantly more effective than the soft-sell letter. However there are several apparent differences in effectiveness by age and by gender. The standard letter is clearly more effective for younger drivers but the soft-sell letter appears to be most effective for drivers over age 45. Considering gender, both letters reduce collisions but the standard letter is more effective for men. For women, the standard letter is more effective than the soft-sell letter, but not more effective than no letter. In fact, accident-free survival for women receiving no letter was nominally but not significantly higher than for women receiving either letter. There are no significant differences in moving violations. However, with regard to major traffic violations, those receiving letters had significantly higher violation free survival, although there were also notable differences in effectiveness, by age.

Small bowel cancer. Imaging features and staging

Small bowel neoplasms are relatively rare. This article presents the imaging features of the most frequently encountered small bowel masses, with emphasis on adenocarcinomas and carcinoid tumors. The CT scan findings and correlative barium and angiographic studies of various small bowel tumors are illustrated. The staging of adenocarcinoma of the small intestine is addressed, with attention to the role of CT scans for radiologic staging.

Predictions of hospital mortality rates: a comparison of data sources

BACKGROUND

Comparing hospital mortality rates requires accurate adjustment for patients' intrinsic differences. Commercial severity systems require either administrative data that omit vital clinical facts about patients' conditions at hospital admission or costly, time-consuming abstraction of medical records. The validity of supplementing administrative data with laboratory data has not been assessed.

OBJECTIVE

To compare risk-adjusted mortality predictions using administrative data alone; administrative data plus laboratory values; and the combination of administrative, laboratory, and clinical data.

DESIGN

Retrospective cohort study.

SETTING

30 acute care hospitals.

PATIENTS

46,769 patients hospitalized with acute myocardial infarction, cerebrovascular accident, congestive heart failure, or pneumonia.

MEASUREMENTS

Each patient's probability of dying was estimated by using administrative data only (unrestricted administrative models), administrative data restricted to secondary diagnoses that are unlikely to be hospital-acquired complications (restricted administrative models), restricted administrative data plus laboratory data (laboratory models), and restricted administrative data plus laboratory and abstracted clinical data (clinical models).

RESULTS

The unrestricted administrative models predicted death better than the restricted administrative models (average areas under the receiver-operating characteristic [ROC] curves, 0.87 and 0.75, respectively) and as well as the laboratory models and the clinical models (average areas under the ROC curves, 0.86 and 0.87, respectively). The good mortality predictions obtained by using the unrestricted administrative models result from inclusion of hospital-acquired complications that commonly precede death. The laboratory models ranked 93% of patients and 95% of hospitals in a manner similar to the clinical models; in comparison, rankings provided by the laboratory models were similar to those provided for 75% of patients and 69% of hospitals by the unrestricted administrative models and for 72% of patients and 77% of hospitals by the restricted administrative models.

CONCLUSIONS

Adding laboratory data (often available electronically) to restricted administrative data sets can provide accurate predictions of inpatient death from acute myocardial infarction, cerebrovascular accident, congestive heart failure, or pneumonia. This alternative avoids the cost of data abstraction and the serious errors associated with using administrative data alone.

Transhiatal herniation of colon after esophagectomy and gastric pull-up

Transhiatal herniation of colon is uncommon after transhiatal esophagectomy. Two patients with this complication are presented. Presenting symptoms vary depending on the size and contents of the hernia. Patients may be asymptomatic. The diagnosis is suggested by plain chest radiography, and treatment, in symptomatic patients, is surgical reduction of the hernia via a laparotomy.

Upper airway obstruction and raised intracranial pressure in children with craniosynostosis

In children with craniosynostosis, raised intracranial pressure (ICP) and upper airway obstruction (UAO) are both common features. However, potential interactions between UAO and ICP during sleep are poorly understood. The aim of the present study was to compare the levels of ICP during sleep between a group of patients with syndromic craniosynostosis (with facial involvement and consequent UAO) and a group of control patients with isolated unicoronal synostosis (with no facial involvement and normal upper airways). Polygraphic cardiorespiratory sleep studies with continuous monitoring of ICP were performed during unsedated sleep in 13 children with syndromic craniosynostosis and 7 control patients with isolated unicoronal synostosis only. In the syndromic group, UAO was present in 11 out of 13 patients, with 8 out of 13 having frank obstructive sleep apnoea. In contrast, none of the control patients showed signs of UAO during sleep. There was no evidence of central apnoeas in any of the patients studied. Clinical histories taken from parents tended to underestimate the severity of the respiratory problems. Elevated ICP was seen in 10 of the 13 syndromic patients, with borderline raised ICP in the remaining three cases. In contrast, raised ICP was seen in only 3 of the 7 control patients, with borderline raised levels in 2 of the 7. For both patient groups, ICP was higher during active sleep compared to quiet sleep. Multiple regression analysis showed that ICP during active sleep was dependent upon disease severity (unicoronal/ multiple synostosis) and to the baseline ICP level during quiet sleep. Both raised ICP and airway obstruction were more apparent during active sleep. There was a significant correlation between severity of UAO and increased ICP in active sleep. We conclude that obstructive respiratory problems are frequent in the syndromic patients, and can be severe in a large proportion of cases; intracranial hypertension is also frequent in this group. Further studies are required to investigate the possibility of a causal relationship between upper airway obstruction and raised intracranial pressure.

Surveillance for silicosis, 1993--Illinois, Michigan, New Jersey, North Carolina, Ohio, Texas, and Wisconsin

PROBLEM/CONDITION

Silicosis is an occupational respiratory disease caused by the inhalation of respirable dust containing crystalline silica. Public health surveillance programs to identify workers at risk for silicosis and target workplace-specific and other prevention efforts are currently being field-tested in seven U.S. states.

REPORTING PERIOD COVERED

Confirmed cases ascertained by state health departments during the period January 1, 1993, through December 31, 1993; the cases and associated workplaces were followed through December 1994.

DESCRIPTION OF SYSTEMS

As part of the Sentinel Event Notification System for Occupational Risks (SENSOR) program initiated by CDC's National Institute for Occupational Safety and Health (NIOSH), development of state-based surveillance and intervention programs for silicosis was initiated in 1987 in Michigan, New Jersey, Ohio, and Wisconsin and in 1992 in Illinois, North Carolina, and Texas.

RESULTS

From January 1, 1993, through December 2, 1994, the SENSOR silicosis programs in Illinois, Michigan, New Jersey, North Carolina, Ohio, Texas, and Wisconsin confirmed 256 cases of silicosis that were initially ascertained in 1993. Overall, 185 (72%) were initially identified through review of hospital discharge data or through hospital reports of silicosis diagnoses; 188 (73%) were associated with silica exposure in manufacturing industries (e.g., foundries; stone, clay, glass, and concrete manufacturers; and industrial and commercial machinery manufacture). Overall, 42 (16%) cases were associated with silica exposure from sandblasting operations. Among the 193 confirmed cases for which information was available about duration of employment in jobs with potential exposure to silica, 37 (19%) were employed < or = 10 years in such jobs and 156 (81%) were employed > or = 11 years. A total of 192 primary workplaces associated with potentially hazardous silica exposures were identified for the 256 confirmed silicosis cases. Of these, nine (5%) workplaces were inspected by state health department (SHD) industrial hygienists, 19 (10%) were referred to the Occupational Safety and Health Administration (OSHA) for follow-up, and seven (4%) were routinely monitored by the Mine Safety and Health Administration. Of the 157 (82%) remaining workplaces, follow-up activities determined that 82 were no longer in operation, eight were no longer using silica, 18 were assigned a lower priority for follow-up, six were associated with building trades and could not be inspected because of the transient nature of work in the construction industry, and 43 workplaces were not inspected for other reasons. Fourteen (7%) of the 192 workplaces were inspected. At 10 of the 14 workplaces, airborne levels of crystalline silica were measured; in nine, silica levels exceeded the NIOSH-recommended exposure level of 0.05 mg/m, and in six, airborne silica levels also exceeded federal permissible exposure limits.

ACTIONS TAKEN

Employee-specific and other preventive interventions have been initiated in response to reported cases. In addition, special silicosis prevention projects have been initiated in Michigan, New Jersey, North Carolina, Ohio, Texas, and Wisconsin. To facilitate the implementation of silicosis surveillance by other states, efforts are ongoing to identify and standardize core data needed by surveillance programs to describe cases and the workplaces where exposure occurred. These core variables will be incorporated into a user-friendly software system that states can use for data collection and reporting.

Retreatment of patients with intracranial gliomas by external beam radiotherapy and cytotoxic chemotherapy

Twenty-one patients with recurrent intracranial gliomas were retreated by external beam radiotherapy between 1987 and 1995. Twenty patients received cytotoxic chemotherapy involving CCNU as part of their retreatment. Only five of the 21 patients had received chemotherapy in combination with the initial external beam radiotherapy (RT) prior to recurrence. The different histological groups were analysed and the patients divided into two groups; group I (Grade I and II gliomas) and group II (Grade III, IV and glioblastoma). The overall median survival for all patients was 59 months, with a median survival of 22 months after recurrence. For group I and group II patients, the median survival was 26 months and 13 months after recurrence respectively. It was concluded that some highly selected patients with intracranial gliomas can be retreated safely by carefully planned external beam RT given to a relatively low dose in order to palliate neurological dysfunction and the symptoms of raised intracranial pressure, and to reduce steroid dependency. The results strongly suggest that recovery does occur after initial RT. Retreatment may possibly improve survival in a small proportion of patients. Further studies, including randomized trial designs, quality of life assessment, and neurological symptoms indices, would be required to determine the quantitative benefit of any such treatment policy. The objectives of this study were to determine whether patients received any benefit, such as symptom relief and the allowance of steroid withdrawal, after retreatment, and whether long term survival could be achieved.